English oak, beech and holly: The UK trees at risk as climate warms and rainfall declines

Kew Gardens - a lush, green oasis on the outskirts of London - is listed as a UNESCO World Heritage site. But beneath the tree tops, trouble is brewing.

Back in 2022, a drought hit the region. It was also the hottest year on record in the UK, with temperatures soaring above 40 degrees Celsius in parts of the country.

Those punishing temperatures were bad news for the 130-hectare gardens' 11,000 trees

Water levels deep below the surface of the soil dried out, forcing some trees, more used to temperate climes, to shed their leaves.

Experts believe they lost around 400 trees as a result of that episode of extreme weather.

"A background rate of loss of trees here might be 20 to 40 in a year. We estimate we've lost as many as 400 since since that drought," says Tom Freeth, Head of Living Collection Support at Kew.

"The best way to think about it [is] in tree time: a storm happens over one night, it's quite clear what you've lost the morning after. This is like a much slower moving event than that because you have the drought, but then you continue to lose trees the year after and the year after that."

Spurred by that loss, scientists at Kew have been investigating how the trees will fare long term.

Using new climate models, they have assessed how the plants will respond the rising temperatures and changing weather patterns.

The result is alarming: they believe up to 50 per cent of the garden's trees could be vulnerable to climate change by 2090.

There are around 2,000 species of trees here, but if mean annual temperatures rise, some will be pushed beyond their natural range.

"If we take the worst case prediction offered up by these globally available models it's going to get a lot hotter - up to four degrees, if we talk about mean